C cook E New Member Joined Jan 17, 2011 Messages 28 Gender Male HSC 2011 Apr 12, 2011 #1 Regarding Quadratic functions. Find P if the roots of the equation 3x^2+px-12 = 0 differ by 4. The answer is 0 but I keep getting -12 for some reason.
Regarding Quadratic functions. Find P if the roots of the equation 3x^2+px-12 = 0 differ by 4. The answer is 0 but I keep getting -12 for some reason.
Trebla Administrator Administrator Joined Feb 16, 2005 Messages 8,546 Gender Male HSC 2006 Apr 12, 2011 #2 Let roots be: a, a - 4 Product of roots: a(a - 4) = -4 => a2 - 4a + 4 = 0 => (a - 2)2=0 => a = 2 So roots are 2, -2 Sum of roots: 2 + -2 = -p/3 => p = 0
Let roots be: a, a - 4 Product of roots: a(a - 4) = -4 => a2 - 4a + 4 = 0 => (a - 2)2=0 => a = 2 So roots are 2, -2 Sum of roots: 2 + -2 = -p/3 => p = 0
